A fan site first tweeted an unaired promo for the Grammys in which Gaga and the metal group's performance was teased. Gaga's big news comes on the heels of what's already proving to be an incredible week for the pop star. After a critically acclaimed (and fan obsessed) performance at the 2017 Super Bowl, Gaga announced her world tour for Joanne.

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This is far from Gaga's first time performing at the Grammys. Last year she was on hand to pay tribute to David Bowie, but it will be Metallica's first appearance since 2014. Mother Monster isn't nominated for any awards this year as Joanne was released after the deadline, but the metal group's "Hardwired" is up for Best Rock Song at this year's show.